The way in which things flow is described by referring to the substance's viscosity. The word "viscosity" originates from Latin and means "sticky". If you'd like to investigate viscosity, you can make your own kitchen viscometer with a cup or glass.

Pour each hot liquid from the starting line again. Time the amount of time it takes for the liquid to get to the finishing line.

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Compare your results. Notice that the viscosity decreased when you heated up the liquid. This is useful for scientists to know when making lubricating oils, as it means that in cold temperatures the viscosity will decrease, so they have to improve the lubricating properties to cope with the cold.